Systems and methods for tissue closure

ABSTRACT

A tissue closure device includes a pusher assembly having a drive arm extending from a drive shaft and a needle driver at a distal end of the drive arm, wherein the needle driver is capable of releasably engaging and rotating a suturing needle having a pointed end and a blunt end about a rotational axis and a cartridge having a protective housing and the suturing needle, the cartridge extending from a distal end of a cartridge holder assembly and releasably attached to the cartridge holder assembly. A pointed end of the suturing needle may be positioned within the protective housing before and after a complete rotation of the suturing needle about the rotational axis. A removable electronic module may be provided controlled by an actuator that mechanically engages the drive shaft to rotate the drive shaft and the needle driver, thereby rotating the suturing needle about the rotational axis.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to and is a continuationof U.S. patent application Ser. No. 15/828,422, filed Nov. 30, 2017, nowU.S. Pat. No. 11,033,262, which in turn claims the benefit of priorityto and a continuation of U.S. patent application Ser. No. 15/256,079,filed Sep. 2, 2016, now U.S. Pat. No. 9,962,156, which in turn claimsthe benefit of priority to and is a continuation of U.S. patentapplication Ser. No. 13/900,991, filed May 23, 2013, now abandoned,which in turn claims the benefit of priority to and is a continuation ofU.S. patent application Ser. No. 12/218,633, filed Jul. 17, 2008, nowU.S. Pat. No. 8,469,973, which in turn claims the benefit of priority toand is a continuation of International Patent Application Serial No.PCT/US07/02204, filed Jan. 29, 2007, which in turn claims the benefit ofpriority to U.S. Provisional Patent Application No. 60/763,038 filedJan. 27, 2006. Each of the foregoing patent applications is incorporatedherein by reference in its entirety for any purpose whatsoever.

FIELD

The embodiments disclosed herein relate to a medical device forperforming a procedure on tissue, such as bony tissue. Embodimentsdisclosed herein are appropriate for sternotomy closure, among otherprocedures. More particularly, embodiments disclosed herein are usefulfor the manipulation and control of a suture needle during sternotomyclosure, and methods for using such a device.

BACKGROUND

Surgical procedures present many challenges which can compromise thehealth of the patient as well as the health of the medical professional.For some surgical procedures, such as cardiac surgery and pneumonectomy,access to the organ is generally gained by a sternotomy, a surgicalprocedure in which the sternum is divided with a device such as a saw orother suitable cutting instrument. After performing the sternotomy, thesternum must be re-approximated. The medical professional typicallycloses the sternum using a stainless steel needle with a sharp cuttingpoint onto which is attached a suture comprising a length of relativelyinflexible stainless steel wire, or alternatively, a combination ofstiff stainless steel wire and flexible stainless steel cable. The wire(or combination cable and wire) suture is manually drawn through bothsides of the sternum so that sufficient length of the wire is protrudingfrom both sides of the sternum and there is no longer any slack wirebelow the sternum. After removing the needle from the wire, the medicalprofessional must manually wrap an end of one wire around the other wireeither with their hands or forceps, repeatedly twisting the two ends ofthe wires around each other in a helical or spiral manner. The medicalprofessional then cuts the twisted wires to a desired length and usessurgical tools to bury the sharp, cut, twisted ends of the wires intothe space between the re-approximated edges of the sternum so that thesharp, cut, twisted ends of the wire do not poke into the underside ofthe patient's skin. Typically, between six and eight wire sutures areplaced in the sternum in order to close the sternum along its length.

The prior art sternotomy closure procedures present many problems to themedical professional and the patient. Manual suturing is often difficultbecause the suturing needle must be forced through tough, dense bone.Manual suturing also involves the handling and manipulation of a sharpsuturing needle with an instrument such as a needle forceps, which canresult in inadvertent, accidental needle pricks through a surgeon's ornurse's gloves, posing a potential risk of infection for the surgeon,nurse, staff, and patient. Manipulating an inflexible wire within thechest cavity underneath the sternum and ribcage is often difficult andawkward. For example, traditionally, the surgeon must manually lift thedivided sternum upward when placing a suture through the bone, placinghis or her hand in significant danger of needle puncture because of theforce required to penetrate the bone. In addition, medical professionalsare often stuck by the sharp, cut, twisted ends of the wires, and arethus subjected to the risk of potentially fatal bloodborne infectionssuch as HIV/AIDS and Hepatitis B and C. Furthermore, the direct handlingof the needle can cause the needle to become contaminated withpathogenic bacteria that can cause onset of infection at the site of thesutures. There is also a risk of the needle penetrating the heart andadjacent vessels and structures and causing a serious and often fatalinfection.

Prior art sternotomy sutures for use by medical professionals aredescribed, for example, in U.S. Pat. No. 4,074,732 entitled “WireCutting, Stripping and Twisting Tool;” U.S. Pat. No. 5,089,012 entitled“Surgical Suture, in Particular for Sternotomy Closure;” U.S. Pat. No.5,318,566 entitled “Sternotomy Cable and Method;” and U.S. Pat. No.5,830,234 entitled “Method for Double Wire Sternotomy Suture,” all ofwhich are hereby incorporated by reference herein in their entireties.Prior art stemotomy sutures require the medical professional to usetheir fingers or manual tools to manipulate the sutures and to providean appropriate amount of tension to the sutures. In addition, U.S. Pat.No. 6,923,819 discloses an apparatus and method for surgical suturingwith thread management, the entirety of which is hereby incorporated byreference herein.

Thus, it is evident that there is a need in the art for an apparatus andmethod for sternotomy closure that is safe, reliable, user friendly, andeffective. The present invention provides a solution for this and otherproblems.

SUMMARY

The purpose and advantages of the present invention will be set forth inand become apparent from the description that follows. Additionaladvantages of the invention will be realized and attained by the methodsand systems particularly pointed out in the written description andclaims hereof, as well as from the appended drawings.

To achieve these and other advantages and in accordance with the purposeof the invention, as embodied herein, the invention includes anapparatus and method for joining tissue, such as bony tissue. Accordingto aspects illustrated herein, there is provided a device for joiningtissue that may be used, for example, for stemotomy re-approximationincluding a pusher assembly, and a cartridge. The pusher assembly has adrive arm extending from a drive shaft and a drive mechanism at a distalend of the drive arm. The drive mechanism is capable of releasablyengaging and rotating a suturing needle having a pointed end and a bluntend about a rotational axis. The cartridge includes a protective housingand the suturing needle. The cartridge extends from a distal end of acartridge holder assembly and is releasably attached to the cartridgeholder assembly.

In accordance with a further aspect of the invention, a pointed end ofthe suturing needle is preferably positioned within the protectivehousing before and after a complete rotation of the suturing needleabout the rotational axis. Moreover, if desired, a removable electronicmodule may be provided in the device that is controlled by an actuatorthat mechanically engages the drive shaft to rotate the drive shaft andthe drive mechanism, thereby rotating the suturing needle about therotational axis.

In accordance with a further aspect the invention also provides acartridge for housing a suturing needle that can be used, if desire, forexample, in sternum re-approximation. The cartridge includes a housinghaving a curved shape, an inner wall and an outer wall. The housing alsoincludes a track in the inner wall of the housing whereby the suturingneedle follows a curved path along the track during a revolution of thesuturing needle. The cartridge further includes an aperture defined inthe housing that intercepts the track, wherein the housing shields thepointed end of the suturing needle during at least a portion of therevolution of the suturing needle.

In accordance with another aspect, the invention further provides asuturing needle for use, for example, in sternum re-approximation. Theneedle includes a curved body having a pointed end that is protected atan end of a rotation cycle and a blunt end that engages a suturingmaterial. The suturing material preferably includes a flexible leaderengaged to a wire suture.

In accordance with still another aspect, the invention provides a methodfor joining tissue, such as sternum re-approximation. The methodincludes releasably engaging a cartridge having a protective housing anda suturing needle to a cartridge holder assembly of a tissue closuredevice. The method further includes, placing the tissue closure devicehaving the cartridge and the suturing needle to cause an aperture in thecartridge to be disposed between a first side and a second side of asegment of tissue to be closed, such as a split sternum, wherein apointed end of the suturing needle is positioned within the protectivehousing before and after a complete rotation of the suturing needleabout a rotational axis. The method also includes activating anelectronic module coupled to a pusher assembly that releasably engagesthe suturing needle to cause rotational movement of the suturing needleacross the aperture in the cartridge and advance the suturing needlethrough the first side of the tissue segment and pulling a suturingmaterial attached to the suturing needle through the first side of thetissue segment. The method further includes using the device to completea stitch through the second side of the tissue segment.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and are intended toprovide further explanation of the invention claimed.

The accompanying drawings, which are incorporated in and constitute partof this specification, are included to illustrate and provide a furtherunderstanding of the method and devices of the invention. Together withthe description, the drawings serve to explain the principles of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The presently disclosed embodiments will be further explained withreference to the attached drawings, wherein like structures are referredto by like numerals throughout the several views. The drawings shown arenot necessarily to scale, with emphasis instead generally being placedupon illustrating the principles of the presently disclosed embodiments.

FIG. 1 is a pictorial view of the main components of a tissue closuredevice provided in accordance with the invention.

FIG. 2A and FIG. 2B are perspective views of a front end assembly of thetissue closure device of FIG. 1.

FIG. 3A shows an expanded view of a pawl. FIG. 3B and FIG. 3C show anexpanded view of a pusher assembly with the pawl in place.

FIG. 4 shows an expanded view of a curved tissue closure needle.

FIG. 5A is a perspective view of the relative configuration of a tissueclosure needle with respect to the pusher assembly. FIG. 5B and FIG. 5Care sectional views of the tissue closure needle and the pusherassembly.

FIG. 6 is a perspective view of a cartridge holder assembly of thetissue closure device of FIG. 1.

FIG. 7 shows an expanded view of a needle cartridge.

FIG. 8A shows an expanded view of an anti-rotate and locking bar. FIG.8B shows an expanded view of the relative configuration of theanti-rotate and locking bar with respect to a suturing needle housed ina needle cartridge.

FIG. 9 shows close-up view of an alternative cartridge locking mechanismutilizing a retractable pin incorporated into the cartridge holderassembly instead of a locking bar.

FIG. 10 shows an isolated view of the cartridge locking pin of FIG. 9.

FIG. 11 shows a cutaway view of the cartridge locking pin of FIG. 9engaged with the locking pin recess of the cartridge.

FIG. 12 shows the locking pin recess of FIG. 11 on the proximal surfaceof the needle cartridge.

FIG. 13 shows an anti-rotate bar without the locking bar feature, whichcan be used when the locking pin feature of FIG. 9 is incorporated intothe cartridge holder assembly.

FIG. 14A shows a perspective view of the relative configuration of theneedle cartridge with respect to the cartridge holder assembly and theanti-rotate and locking bar before the needle cartridge has been lockedinto place. FIG. 14B shows a perspective view of the relativeconfiguration of the needle cartridge with respect to the cartridgeholder assembly and the anti-rotate and locking bar after the needlecartridge has been locked into place.

FIG. 15 shows a suture retainer on the top side of the cartridge, usedto hold the suture material away from the needle, drive arm and pawl ofthe needle pusher assembly.

FIG. 16 shows a rearward-leaning perspective view of the front of thecartridge, revealing the recess of the suture retainer of FIG. 15 intowhich the suture can be placed.

FIG. 17 shows the suture material in cross-section, placed within therecess of the suture retainer of FIG. 15.

FIG. 18 shows a top view of the needle cartridge and suture retainer ofFIG. 15, revealing the detents of the suture retainer projections thathold the suture material within the recess.

FIG. 19 shows a needle brace that can be installed on the needlecartridge from the outside/distal surface of the cartridge.

FIG. 20 shows the needle brace of FIG. 19 installed against the needlecartridge.

FIG. 21 shows a rear perspective view of the needle brace of FIG. 19installed in the cartridge, revealing its positioning adjacent to theblunt and pointed ends of the suturing needle.

FIG. 22 shows an alternative design of the needle brace of FIG. 19, inwhich the stop at the pointed end of the needle comprises a flexibletab, which can aid in securing the brace onto the cartridge.

FIG. 23 shows the needle brace of FIG. 22 installed onto the cartridge,showing the flexible tab snapped onto the point of the needle.

FIG. 24 shows an electronic module of the tissue closure device of FIG.1.

FIGS. 25 A-H show various perspective views of the electronic module ofthe tissue closure device of FIG. 1, including a left front perspective(A), front perspective (B), right front perspective (C), left rearperspective (D), rear perspective (E), right rear perspective (F), topperspective (G) and bottom perspective (H).

FIG. 26A, FIG. 26B and FIG. 26C show views of a tissue closure devicewherein the electronic module has been encased in a housing.

FIGS. 27 A-F show the installation of the funnel into the back end ofthe handle of the suturing device, with the funnel aligned with thebarrel of the handle (A and D), the funnel in position within the handle(B and E), and the electronic module of FIG. 24 aligned with theinstalled funnel (C and F).

FIGS. 28 A-F show various perspective views of the funnel of FIG. 27 inisolation, showing the rear (A), front (B), right side (C), left side(D), top (E) and bottom (F) of the funnel.

FIG. 29 shows the electronic module of FIG. 25 showing an alternativearrangement of the power and actuation buttons and indicator LED's.

FIG. 30 shows an enlarged view of a drive wheel and a stop plate. Adrive pin penetrates the stop plate and rides in a “U-shaped” track.

FIG. 31A, FIG. 31B, and FIG. 31C show segmented sectional views of themain components of the tissue closure device.

FIG. 32A shows an embodiment of a tissue closure needle having thetissue closing suture material attached thereto. FIG. 32B shows anexpanded view of a crimp that houses the ends of the two materials thatform a tissue closure suture material.

FIGS. 33 A-C show details of the construction of the pointed end of thetissue closure needle of FIG. 4, with the distribution of the facets(A), the angle of the outer curvature facet (B), and the resulting shapeof the needle point (C).

FIG. 34 shows a disposable paper and plastic film package enclosing thesterile needle cartridge of FIG. 7, and the suturing needle and attachedsuture material of FIG. 32A.

FIG. 35 shows an embodiment of a tissue closure device of the presentlydisclosed embodiments.

FIGS. 36 A-C show front perspective views of an embodiment of thesuturing device of FIG. 1, with needle cartridge attached, includingleft front (A), front (B), and right front (C) perspectives.

FIGS. 37 A-D show other perspective views of the suturing device of FIG.36, without an attached cartridge, including left rear (A), right rear(B), bottom (C) and top (D) perspectives.

FIG. 38 shows a further embodiment of a tissue closure device providedin accordance with the invention.

FIGS. 39A-39D shows the operation of the driver arm in the cartridgeholder assembly operating in a rear drive mode.

FIG. 40 shows an embodiment of a tissue closure device placed at asternotomy site such that the device is between a first side and asecond side of a split sternum.

While the above-identified drawings set forth presently disclosedembodiments, other embodiments are also contemplated, as noted in thediscussion. This disclosure presents illustrative embodiments by way ofrepresentation and not limitation. Numerous other modifications andembodiments can be devised by those skilled in the art which fall withinthe scope and spirit of the principles of the presently disclosedembodiments.

DETAILED DESCRIPTION

Reference will now be made in detail to the present preferredembodiments of the invention, examples of which are illustrated in theaccompanying drawings. The method and corresponding steps of theinvention will be described in conjunction with the detailed descriptionof the system.

The devices and methods presented herein may be used for tissue closure.The present invention is particularly well suited for proceduresinvolving bony tissue, such as sternotomy closures. As depicted, thedisclosed tissue closure device, or suturing device, is a motorized,electrically powered apparatus. The power source can be battery orstandard wall electrical power. The tissue closure devices disclosedherein advantageously prevent accidental needle punctures to the medicalprofessional and readily and easily drive needles through bony tissue,eliminating the need to manually force the needles through the bone.Within the context of sternotomy closure, the disclosed devices protectthe heart and adjacent vessels and structures from inadvertent needlepunctures during closure and replicates the standard sternotomy closuretechnique. In so doing, the disclosed embodiments provide easier andmore fluent manipulation of the wire or wire/cable combination withinthe chest cavity or other anatomy, and produce tissue closure in a timeefficient manner so the patient is not subjected to health risksassociated with having a tissue segment, such as the sternum, open formore time than necessary.

The main components of a tissue closure device of the presentlydisclosed embodiments are shown generally at 50 in FIG. 1. The tissueclosure device 50 can be used to produce a continuous, or more commonly,an interrupted suture so as to enable closure of the sternal halvesafter a sternotomy procedure, for example. As depicted, device 50 is amotorized, battery-powered apparatus designed to prevent needlepunctures during sternotomy closure or other similar procedures. Device50 delivers reliable closure using standard needles and wires andreplicates standard tissue (e.g., sternotomy) closure techniques. Device50 easily drives needles through bone as well as other tissue, thuseliminating the need to manually force the needles through the bone; andprotects the heart and adjacent vessels and structures from inadvertentneedle punctures during closure.

Referring to FIG. 1, the tissue closure device 50 includes a removableelectronic module 60 including a battery pack 62, an electric motor 61,and a gear box 59, as well as electronic circuits. The gear box 59further includes a shaft that runs through a stop plate 66, a bearingsurface 68, and a drive wheel 67. A drive pin 63 engages the drive wheel67 and when in use, mates with a hole in a drive plate 80 that is partof a front end assembly 70. The bearing surface 68 acts as a lubricatingsurface between the stop plate 66 and the drive wheel 67. The bearingsurface 68 may be any lubricious material having a low coefficient offriction, for example fluoropolymer compounds such as those includingpolytetrafluoroethylene (PTFE).

The electric motor 61 preferably is compact yet powerful. In oneembodiment, a DC motor can be selected from the Maxon RE-max 29 series,for example, commercially available from Maxon Precision Motors, Inc. ofFall River, Mass. Model no. 226784 can be used, which weighs 159 grams,is 29 mm in size, operates on 9 volts, can generate 22 watts, and has ano-load speed rating of 7630 RPM. The gear box 59 can be selected from,for example, the Maxon Gearhead GP32C series, which is 32 mm is size.Model no. 166943 can be used, which has 3 stages, weighs 194 grams, andhas a 103:1 gear reduction ratio.

As depicted, the front end assembly 70 includes a pusher assembly (notvisible) and a cartridge holder assembly 72. The pusher assembly has adrive arm that houses a drive mechanism (“pawl”) and a drive shaft thatruns throughout the length of the front end assembly 70 and enters thedrive plate 80. A needle cartridge 90 carrying a tissue closure needle110 may be removably attached to a distal end 81 of the cartridge holderassembly 72.

FIG. 2A and FIG. 2B show the front end assembly 70 including a pusherassembly 71 and the cartridge holder assembly 72 with the attacheddisposable needle cartridge 90 which houses the tissue closure needle110. The pusher assembly 71 includes a drive shaft 73 and a drive arm 75that is in intimate contact with the needle 110 via a pawl. The driveshaft 73 engages a spline in the drive plate 80 so the drive shaft 73 isrotationally attached to the drive plate 80. When the electronic moduleis attached to the front end assembly the drive shaft 73 engages abushing located in the drive wheel 67. The cartridge holder assembly 72(shown in FIG. 2B) includes a shaft barrel 74 and a support arm assembly76 that is comprised of a pair of “skeletalized” arms extending alongmutually divergent axes so as to provide an opening 78 to view thedevice 50 during its operation. The open configuration of the supportarms 76 are minimal in bulk and provide a relatively wide opening 78that allows the medical professional to directly view the aperture inthe needle cartridge 90 and cartridge holder assembly 72, the space, forexample, between a first side and a second side of a split sternum andneedle advancement through the space during operation of the tissueclosure device 50. Although the embodiment shown in FIG. 2 has aplurality of support arms 76, other variants include a support armassembly comprising a single support arm. The improved viewing abilityoffered by the shape and configuration of the support arm assembly 76enables precise device placement over the sternum in the case of asternotomy closure procedure, and uniform advancement of the tissueclosure device 50 after every stitch to provide a uniform and symmetricsuture, thereby protecting the heart and adjacent vessels and structuresfrom inadvertent needle punctures during closure.

The distal end 81 of the cartridge holder assembly 72 is where theneedle cartridge 90 is disposably attached. The needle cartridge 90comprises a circular housing that may be formed of a suitable rigidmedical grade sterilizable metal or plastic material. Preferably, thematerial forming the cartridge 90 possesses both rigidity and a lowcoefficient of friction to reduce the power required to move the needledisposed within it. One such material, for example, is Lubricomp DFP22H,produced by GE Plastics, a polycarbonate containing 10% glass fill, 8%PTFE (Teflon), and 2% silicone. Constructing the cartridge from thismaterial can provide for up to 20% more driving power at the point ofthe needle. The housing may be releasably retained by the distal end 81of the cartridge holder assembly 72 by known means, such as a pluralityof grooves located along on the edge of an inner lip in diametricallyopposite positions that are capable of engaging the same plurality ofslots correspondingly located in the distal end 81 of the cartridgeholder assembly 72. The grooves when engaged enable the needle cartridge90 to be retained by the distal end 81 of the cartridge holder assembly72. A torsion return spring 77 engages the shaft barrel 74 and the driveplate 80 and is responsible for returning the drive shaft 73 back to a“start” position such that when the electronic module 60 is attached tothe front end assembly 70 the drive pin 63 will properly engage thedrive plate 80 of the front end assembly 70.

As best shown in FIG. 31A and FIG. 31B, O-rings 57 between the pusherassembly 71 and the cartridge holder assembly 72 create a separationbarrier to ensure the device 50 stays sterile during operation. Thefirst O-ring 57 seals the rotating shaft against the front end assembly.The second O-ring 57 seals closer to the housing and seals the front endassembly against the nose collar 157. The plurality of O-rings 57provide a sterile barrier to seal the device exterior from the interiorof the handle. Alternatively, as shown in FIG. 31C, a Teflon seal 57Acan be used, which provides for a more durable barrier to the entry andexit of fluids and other possible contaminants. The barrier sealeliminates means of exiting of any non-sterile germs, debris, particles,etc., from the inside of the device to the sterile outside of the devicefront end.

FIG. 3B and FIG. 3C show expanded views of the pusher assembly includinga pawl 95 (as shown in FIG. 3A) located at the tip, which resides in aslot in the drive arm 75 of the pusher assembly, and is connected to thedrive arm 75 by a pivot pin 99. The needle (not shown) is driven in acircular path by the pawl 95.

FIG. 4 shows an embodiment of the curved tissue closure needle 110 ofthe presently disclosed embodiments, which is particularly suitable forpenetration through bony material. The needle 110 is formed as acircular split ring defining an aperture (or gap) 111, a sharp, pointedend 112 and an opposite blunt end 113. A cylindrical bore 114 alignedaxially with respect to the needle 110, is located at the blunt end 113.The leading end of the suturing material for tissue closure is insertedinto the bore 114 and restrained by mechanically crimping.Alternatively, the opening for accommodating the suture material can bein the form of an “eye” wherein the leading end of the suturing materialmay be passed through for attaching it to the needle 110. To enable theneedle 110 to penetrate to the required depth, the needle 110 preferablyhas an arcuate extent between about 250° and about 330°.

The needle 110 further includes two symmetric notches 115 a and 115 balong the radially rear edge, i.e. the edge proximal to the cartridgeholder assembly. The notch 115 b is positioned toward the sharp pointedend 112 of the needle 110. The notch 115 a is positioned toward theblunt end 113 of the needle 110. The notches 115 a and 115 b are locatedopposite to one another, each having a perpendicular (about 90°) segmentand an angular segment that makes an angle of about 60° with theperpendicular segment. The notches 115 a and 115 b are engaged by thedrive mechanism (pawl) in the cartridge holder assembly 72 and enablethe needle 110 to undergo a rotational movement upon actuation of thedrive mechanism, thereby causing it to penetrate and advance through thespace spanning the tissue segment, such as a split sternum. A notch 116is located on the radially outer edge (“outer notch”) of the needle 110proximally to the notch 115 b that is closer to the sharp, pointed end112. The outer notch 116 engages with an anti-rotate bar located in thecartridge holder assembly 72, whereby rotation of the needle 110 in adirection opposite to the advancing direction or “needle backing-up” isprevented. The positive engagement of the needle outer notch 116 duringoperation prevents the needle 110 from straying out of sequence duringthe suturing process.

The needle 110 is enclosed within a cartridge, so the sharp pointed end112 is not exposed. This needle position, as loaded, is referred to asthe “home” position. In the home position, the needle 110 is fullycontained within the cartridge housing to eliminate needle-pricks duringhandling of the cartridge or the loaded device. The width of theaperture in the needle cartridge is comparable to and corresponds withthe width of the gap in the needle 110 so that when the needle 110 is inthe home position the needle 110 does not project materially into theaperture 111. Such an alignment causes the needle 110 to reside entirelywithin the needle cartridge, thereby preventing inadvertent contact ofthe sharp pointed end 112 with the user's fingers during handling of thedisposable needle cartridge for placement on the cartridge holderassembly or disposal after use, and while operating the tissue closuredevice 50. Such protection of the needle 110 in the tissue closuredevice 50 prevents accidental “needle-pricks” from occurring, therebysubstantially reducing the risk of infection caused by pathogenicbacteria or viruses that may contaminate the needle 110 during or afteruse prior to disposal. The needle 110 may be rotated in a curved trackof the needle cartridge about the longitudinal axis of the suturingdevice 50 to advance the pointed needle end 112 so that the needle 110first spans the aperture 111 and then returns to the home position. Thesuturing material is attached to the needle 110, and therefore followsthe path of the needle 110. The suturing material may then be cut andtwist tied and secured by an appropriate method. Every stitch, whether asingle, interrupted stitch, or one of a series of continuous, runningstitches may be placed in like manner. The tissue closure, or suturingdevice 50, therefore, may be used to insert either a single stitch, orto insert a suture comprising a plurality of continuous stitches as areplacement method for a more tedious and time-consuming manual suturingprocess.

FIG. 5A provides a detailed view of the pusher assembly 71 with relationto the suturing needle 110. The pawl at the tip of the drive arm 75 iscapable of interfitting with wedge shaped notches located along theradially inner edge of the needle 110. The drive arm 75 is capable ofsweeping back and forth in an arc spanning about 190°. The drive armrotates more than 180°, and the overdrive accounts for any designirregularities and tolerances on the needle 110 and the moving parts andensures that the pawl will always pick up the needle notch 116.

The advancing movement of the needle 110 during operation causestriangular slots along the radially inner edge of the needle 110 toalign with the wedge-shaped pawl in the drive arm 75, thereby causingthe pawl to engage the slots due to a positive pressure exerted on thepin 99, and to “lock” into the slots. The rotatory advancing movement ofthe needle 110 is therefore controlled to occur sequentially throughabout 190° each time the tissue closure device 50 is actuated. For eachsuture stitch, the needle 110 rotates through an arc of about 360°,while the drive arm 75 rotates back and forth for a total of about 760°degrees per stitch.

FIG. 5B and FIG. 5C are sectional views of the tissue closure needle andthe pusher assembly. As shown in FIG. 5B, a flat spring 96 assertstension on the pawl 95 to push the pawl 95 distally into the needle 110and into the notch 115 b. When the pawl 95 is rotated, the pawl 95 picksup that notch 115 b and drives the needle 110.

FIG. 5C shows the pawl 95 not engaged in the notch 115 b and engagingthe surface of the needle 110. As the pawl 95 moves along the outersurface of the needle 110, the pawl 95 encounters the notch 115 b. Thepawl tip engages the ramp for the notch 115 b and the flat spring 96pushes the pawl 95 into the needle notch 115 b.

FIG. 5C shows a pawl stop 98 that permits the pawl tip to only extend acertain amount into the needle 110 to not bind the needle 110 and causethe needle 110 to stop. The pawl 95 has an angled surface that anglesaway from the pawl stop 98. When the pawl 95 rotates clockwise, the pawl95 can only turn until the angled surface contacts the pawl stop 98. Thepawl 95 contacting the pawl stop 98 is shown in FIG. 5B. The pawl stop98 prevents further rotation of the pawl 95 and prevents the pawl 95from binding the needle 110 in the cartridge 90.

FIG. 6 shows a close-up view of the distal end 81 of the cartridgeholder assembly 72. The cartridge holder assembly 72 is composed of asterilizable medical grade material which can either be a metallicmaterial such as stainless steel to enable its reuse subsequent tosterilization following a prior use, or a sterilizable medical gradeplastic material, in which case, it may be discarded and disposed aftera single use. The cartridge holder assembly 72 has a cylindricalconfiguration with a distal edge 87 and a proximal edge 89 with respectto the device actuator handle (not shown), with an aperture 85 thatcorresponds in dimension and location to coincide with a substantiallysimilar aperture located in the disposable needle cartridge. Thecartridge holder assembly 72 additionally comprises a plurality of slots82 located along on the distal edge 87 that are located opposite to oneanother, and are capable of engaging the same plurality of retainingclips correspondingly located in the needle cartridge housing (notshown). The cartridge holder assembly 72 further comprises a cylindricalslot (not visible) located on the distal edge 87 that is capable ofengaging a pivoting pin of identical diameter correspondingly located ona gate assembly 105. The proximal edge 89 of the cartridge holderassembly 72 is attached to the shaft segment 74 by the support armassembly 76. The gate assembly 105 prevents the needle from leaving thetrack and falling out into the back of the cartridge holder assembly 72.The gate assembly 105 pivots on a pivot pin 107 like a rocker switchduring each actuation of the tissue closure device 50 to permit acircular movement of the drive mechanism that engages the needle. Stoppins 106 located on the cartridge holder assembly cause the gateassembly 105 to stop and reverse direction, like a “see-saw,” “up-down”motion. The gate assembly 105 precludes the lateral movement anddislocation of the needle within the cartridge holder assembly 72. Thegate assembly 105 is able to pivot on the pivot pin 107 so that thedrive arm 75 which engages with the needle via the pawl can pass by thegate assembly 105. An anti-rotate bar 100 is capable of engaging withthe needle cartridge 90 to lock it in place on the cartridge holderassembly 72 as well as to engage the needle, whereby rotation of theneedle in a direction opposite to the advancing direction or “needlebacking-up” is prevented.

FIG. 7 shows a close-up view of a disposable needle cartridge 90 of thepresently disclosed embodiments, which is preferably offered in asterilized sealed package. The needle cartridge 90 comprises a circularhousing 91 that may be formed of a suitable rigid medical gradesterilizable metal or plastic material. The material forming thecartridge 90 preferably has both rigidity and a low coefficient offriction to reduce the power required to move the needle disposed withinit. One such material, for example, is Lubricomp DFP22H, produced by GEPlastics, a polycarbonate containing 10% glass fill, 8% PTFE (Teflon),and 2% silicone. Constructing the cartridge from this material canprovide for up to 20% more needle driving power at the point of theneedle. The housing 91 may be releasably retained by the cartridgeholder assembly at the distal end of suturing device 50 by known means,such as a plurality of grooves 94 in diametrically opposite positionsthat are capable of engaging with the plurality of slots on the distaledge of the cartridge holder assembly. The needle cartridge 90 furthercomprises a groove 93 that is capable of engaging the anti-rotate andlocking bar 100 correspondingly located on the cartridge holderassembly.

While the grooves 94 when engaged enable the needle cartridge 90 to beretained by the cartridge holder assembly, the groove 93 when engagedwith the anti-rotate and locking bar 100 causes an aperture 97 definedin the needle cartridge 90 to be aligned with the corresponding aperturein the cartridge holder assembly. The needle cartridge 90 furthercomprises a circular groove or “track” 92 that is inscribed in theinside surface of the housing 91, which lies in a plane that isperpendicular to the longitudinal axis of both the housing 91 and thatof the suturing device 50. The aperture 97 interrupts the track 92.

The arcuate suturing needle 110 composed of medical grade stainlesssteel or similar material is slidably positioned in the track 92. Theradius of the arc defining the arcuate needle 110 is approximately equalto the circumference to the needle cartridge 90 at the aperture 97therein. The needle 110 normally resides in a “home” position in thetrack 92 such that the gap in the arcuate needle 110 is in alignmentwith the aperture 97 in the cartridge 90. The sharp, pointed end of theneedle 110 is situated on one side and entirely within the confines ofthe housing aperture 97; the pointed end of the needle 110 is,therefore, shielded by the cartridge housing 91. The blunt end of theneedle 110 that is attached to a suturing material is located at theopposite side of the aperture 97. The sharp, pointed end of the needle110 is, therefore, wholly contained within the cartridge 90 and does notprotrude beyond the housing of the cartridge 90. Thus, the sharp pointedend of the needle 110 is not exposed to the user.

FIG. 8A shows a close-up view of the anti-rotate and locking bar 100. Asshown in FIG. 8B, the anti-rotate and locking bar 100 includes acartridge locking surface 101, which makes contact with the needlecartridge 90 and locks it into place, and an anti-rotate surface 102,which contacts the needle 110. A coil spring 104 engages the cartridgeholder assembly 72 and allows the anti-rotate and locking bar 100 tomove up and down so as to lock or un-lock the needle cartridge 90 intoplace on the cartridge holder assembly 72.

FIGS. 14A and 14B show an enlarged view of the distal end 81 of thecartridge holder assembly 72. In FIG. 14A, the needle cartridge 90 is ina non-locked position. In order to lock the needle cartridge 90, theneedle cartridge 90 needs to be rotated counter clockwise. To unlock theneedle cartridge 90 from the distal end 81 of the cartridge holderassembly 72, the anti-rotate and locking bar 100 may be pressed down toengage the coil spring and this will allow the anti-rotate and lockingbar 100 to pivot at pivot pin 103.

FIG. 9 shows an alternative cartridge locking mechanism. A locking pin200 is slidably disposed within the cartridge holder assembly 72. Ahandle and button 203 connected to the locking pin 200 allows theoperator to slide the pin 200 proximally along the slot 204 from aposition that protrudes from the distal edge 87 of the cartridge holderassembly 72 to a fully retracted position (not shown). As shown in thecross-sectional view of FIG. 11, the locking pin 200 is biased toprotrude from the distal edge 87 of the cartridge holder assembly 72 byvirtue of the spring 201 situated on the proximal end of the locking pin200. When the needle cartridge 90 is secured to the cartridge holderassembly 72, whereby the grooves 94 are fully engaged with the slots 82,a locking pin recess 202 on the mating surface of the cartridge 90aligns with the pin 200, allowing the pin 200 to protrude and engage therecess 202, thereby locking the needle cartridge 90 rotationally ontothe cartridge holder assembly 72. The locking pin recess 202 is formedto be slightly larger but with a similar cross-sectional shape as thelocking pin 200. In one embodiment, the cross-sectional shape of thelocking pin 200 and the shape of the locking pin recess 202 arecircular. To release the cartridge from the cartridge holder assembly, auser can engage the handle and button 203 attached to the pin 200 andslide the pin 200 proximally to retract it from the locking pin recess202. Upon retracting the locking pin 200, the user can rotate the needlecartridge 90 to disengage the grooves 94 from the slots 82, and therebyremove the cartridge from the cartridge holder assembly 72. The lockingpin recess 202 is more clearly seen in FIG. 12, a perspective view of aportion of the mating or proximal surface of the needle cartridge 90.

The anti-rotate and locking bar 100 engages the outer notch of theneedle 110 to prevent rotation of the needle 110 and prevent “needlebacking-up” and thereby precluding the needle 110 from straying out ofsequence. FIG. 14B shows the needle cartridge 90 locked into positionboth rotationally and axially.

The construction of the anti-rotate and locking bar 100 can besimplified if the cartridge locking function is achieved with a lockingpin 200. The arm leading to the locking surface 101 of the anti-rotateand locking bar 100, can be eliminated, resulting in a purelyanti-rotate bar 300, as shown in FIG. 13. The anti-rotate bar 300 cancomprise an anti-rotate surface 302 that makes contact with the needle110. The anti-rotate bar 300 is biased by spring 304 to engage theanti-rotate surface 302 with the outer notch 116 of needle 110 toprevent reverse rotation of the needle 110.

As shown in FIG. 15, the cartridge 90 can be equipped with a sutureretainer 400 to keep the suture material 138 from interfering with therotation of the needle 110 during operation of the suturing device 50.The suture retainer 400 helps to keep the suture material 138 away fromthe needle track 92 of the cartridge 90. A front perspective view of theneedle retainer 400 is shown in FIG. 16. The projections 401 help theoperator to guide the suture material 138 into the needle retainerrecess 402 of the cartridge 90. As shown in FIG. 17, the detents 403 ofthe needle retainer 400 cause the passageway to the needle retainerrecess 402 to be slightly smaller than the diameter of the suturematerial 138, allowing the operator to press-fit the suture material 138into the needle retainer recess 402. This is also shown in FIG. 18,illustrating how the detents 403 provide a slightly narrower passagewayfor the suture material into and out of the needle retainer recess 402.This feature prevents the suture material 138 from unintentionallyslipping out of the needle retainer 400.

The needle cartridge 90 can also be equipped with a needle brace 500, asshown in FIG. 19. Positioning a needle brace 500 against the cartridge90 can prevent inadvertent movement of the needle 110 within thecartridge 90 during handling of the cartridge 90 and suture material 138prior to loading the cartridge 90 onto the cartridge holder assembly 72.This keeps the needle 110 from straying within the track to a positionplacing it out of proper sequence for initiation of the first actuationcycle of the suturing device 50. The needle brace 500 has a flange 501that contacts the outside (distal) surface of the needle cartridge 90holding the brace in position, as shown in FIG. 20. The needle brace 500has a body 502 whose outside radial dimension conforms to the insideradial dimension of the cartridge 90, allowing a shoulder feature 503 ofneedle brace 500 to be situated near the inside (proximal) surface ofcartridge 90 and adjacent to the hub or blunt end of needle 110 seatedwithin the cartridge 90, as shown in FIG. 21. The needle 110 is thusprevented from rotating within its track in a reverse direction.Similarly, the pointed end of needle 110 is prevented from movingforward in its track by the presence of the vertical segment 504 of body502 of needle brace 500, which closely conforms to the inside radialdimension of cartridge 90 and blocks the forward movement of needle 110in its track. With the needle brace 500 in position, an individual canmanipulate the cartridge/needle/suture assembly without fear ofinadvertently moving the needle within the track of cartridge 90. Suchmovement could potentially position the needle out of proper sequencefor activation after it is placed on the cartridge holder assembly 72.The needle brace 500 may be formed of a suitable rigid medical gradedisposable metal or plastic material.

The needle brace 500 can be secured within the inner circumference ofthe cartridge 90, either through a frictional ‘press’ fit, or throughtabs placed along the periphery of the needle brace 500, which cancooperate with corresponding depressions (not shown) along the innercircumference of the cartridge 90. In a further refinement of the needlebrace 500, the vertical segment 504 can be constructed so that it formsa tab 504A as shown in FIG. 22. The tab 504A is constructed of materialwith sufficient elastic properties to be somewhat bendable. TheLubricomp plastic material referenced earlier, for example, possessesthis characteristic. With the pointed end of needle 110 positioned atthe end of the track of cartridge 90, installing needle brace 500 causesthe tab 504A to bend slightly and snap into position over the tip of theneedle 112, thereby locking the needle brace 500 into position, as shownin FIG. 23. A user can remove the needle brace 500 by applyingsufficient force to overcome the elastic resistance of the tab 504 a.

FIG. 24 is an exploded perspective view of the removable electronicmodule 60 which is a battery-operated electro-mechanical assembly. Theelectronic module 60 includes the battery pack 62 and the electric motor61 which includes the gear box 59 and an output shaft 58, as well aselectronic circuits. The battery 62 is preferably re-chargeable andprovides the power for the electronic module 60. The battery 62 shouldhave a minimum battery life of about 400 discharge cycles and be able toperform 18 sutures (or 36 total cycles) through a tissue segment such asthe sternum. The motor 61 provides the rotational force necessary forthe tissue closure device 50 to function. An electronics board controlsthe operation of the electronic module 60 based on user controlled powerand actuation buttons. Indicators are provided to provide feedback tothe user of the current status of the electronic module 60. Amicroprocessor and firmware control the starting, stopping, and torqueof the electric motor 61. The electronics also includes the rechargingcircuit for the battery pack 62. The electronic module 60 may beprovided as non-sterile and may be attached to the front end assemblyprior to surgery by an aseptic technique. The electronic module 60 maybe removed from the front end assembly following a procedure forcleaning, battery charging and storage. Additional views of theelectronic module 60 are shown in FIG. 25(A) to 25(H).

FIGS. 26A and 26B show the tissue closure device 50 wherein theremovable electronic module 60 has been enclosed in a thermoplasticenclosure 150 and a thermoplastic housing 151. A door 152, locked by aclamp latch 153, provides entry and exit for the removable electronicmodule 60. The handle 160 of the device has the door 152 at the proximalend where the removable electronic module 60 is inserted. When thenon-sterile battery pack is installed, the door 152 needs to be closedand sealed. The door 152 is sealed using an O-ring or Teflon sealsimilar to the front end of the device to prevent the egress of anynon-sterile germs from the inside the device into the sterile operatingfield.

In order to facilitate the placement of a non-sterile electronic module60 into a sterile handle 160, a funnel 600 can be provided, which istemporarily placed within the opening of the proximal end of the handle160, as shown in FIGS. 27(A-F). The funnel 600 operates as a physicalbarrier between the person (e.g. circulating nurse) who handles thenon-sterile electronic module 60 and the person (e.g. surgical scrubnurse) who handles the sterile components of the suturing device 50. Thesterile components include the handle 160, the door 152, the latch 153,the nose collar 157, the shaft segment 74, cartridge holder assembly 72,and cartridge 90. The funnel 600 is initially sterile when inserted intothe handle 160. As shown in FIGS. 28(A-F), the funnel 600 has a proximalbarrel 601 and a distal barrel 602, each shaped in cross-section toconform to the cross-sectional shape of the handle 160 and correspondingelectronic module 60. The proximal 601 and distal 602 barrels of thefunnel 600 are separated by a flange 603 broad enough to form a barrierbetween the hand of the person inserting the electronic module 60 andthe rest of the suturing device 50. An arrow 604 can be printed orengraved on the surface of the flange to direct the user in installingthe funnel 600 in the proper vertical orientation. The arrow 604 orother suitable printing 605 on the flange 603 can also help the userdistinguish the proximal 601 from the distal 602 barrels of the funnel600. The distal barrel 602 can fit within the handle 160, as shown inFIGS. 27B and 27E. The electronic module 60 can be passed through thecavity of the funnel 600, as shown in FIGS. 27C and 27F. Once theelectronic module has passed through the funnel 600, and has beeninserted into the handle 160, the funnel 600 is no longer considered tobe sterile and can be removed. The door 152 can then be closed in asterile manner and secured with the latch 153, also securing theproximal end of the electronic module 60 in place. The outer surfaces ofthe suturing device 50 remain sterile, a condition facilitated by theuse of the funnel 600. In an alternative embodiment, the funnel 600 canhave a sterile drape (preferably disposable) attached to the peripheryof the flange 603 in order to extend the barrier separating the sterilefrom the non-sterile components and personnel. The mode of attachment ofthe drape to the flange 603 can include, for example, a high strengthadhesive that resists breakdown by heat, moisture and sterilizing gas.

As shown in FIGS. 26A through 26C, a silicone keypad is encapsulatedinto the enclosure 150 and provides two buttons, one for power 154, andone for actuation 155. An alternative electronic module 60 with adifferent arrangement of the keypad buttons is shown in FIG. 29, inwhich the Power-on/Power-off button 154A is separated from the actuationbutton 155A by the LED indicator 156. The electronic keypad 154A and155A, and LED indicator 156 are integral to the battery/motor/gear boxunit, and form the electronic module 60, as shown in FIG. 29. ThePower-on/Power-off button 154 enables the electronic module to either beturned on or off. The actuation button 155 may be depressed which wouldrun the electronic module through one cycle. One cycle consists of a360° needle 110 rotation accomplished through two 190° rotations of theoutput shaft 58. The electronic module 60 interfaces with the enclosure150 through the stop plate 66 mounted to the front of the electronicmodule 60. The stop plate 66 has flat faces and a taper to engage intothe enclosure 150. This provides the connection to capture the torqueapplied within the unit so that the operator does not have to oppose thetorque of the suturing operation (anti-rotation feature). The stop plate66 also limits the rotation travel of the output shaft 58 to about 190°.A drive wheel is attached to the output shaft of the electronic module60. The drive wheel contains a drive pin which engages with the driveplate of the front end assembly 70. The drive pin supplies the torque tothe front end assembly 70 to drive the needle 110 through the tissue.The drive wheel also contains two permanent magnets. These magnets arepreferably used in conjunction with a Hall Effect sensor 162 to detectthe rotational extents of travel. A nose collar 157 attaches the frontend assembly 70 to the housing 151 via screws 158 or some other meansfor mechanical engagement.

Three indicators (LEDs) 156 show the status of the unit: Power (Green),Error (Red) & Low Battery (Yellow). The housing 151 and keypad providean exterior surface that is capable of sustaining hospital wipe-downprocedures, but is not sterilizable in an autoclave. The electronicmodule software and operating features cause the needle driver arm toautomatically move to its home position (reverse motion limit) when thePower-on/Power-off button 154 is initially activated (depressed). Theunit will turn itself off after 10 minutes of inactivity in the event itis stored with the power on. Depressing the Power-on/Power-off button154 during an actuation cycle will be ignored by the software. When theelectronic module is switched On, the On LED indicator will illuminateand remain illuminated until switched Off. In one embodiment, triggeringan actuation cycle to drive the needle through tissue by depressing theactuation button 155 will cause the device 50 to automatically power offat the end of the cycle. Once switched On or Off, the electronic modulewill stay in that condition until deliberately switched to the oppositecondition, unless there is an error mode, the electronic moduletimes-out from inactivity, or an actuation cycle has occurred. Theelectronic module has an Error LED (color red) to indicate an ErrorMode. The electronic module also has a Low Battery LED (color Yellow)which indicates the internal battery needs to be charged. The actuationbutton 155 must be depressed for the device 50 to drive the tissueclosure needle 110. The actuation cycle begins when the actuation button155 is depressed. The actuation button 155 does not have to remaindepressed (i.e. the actuation cycle will complete if the button isreleased). The actuation button 155 only requires one depression torotate the needle 110 360° (the needle driver arm will automaticallyrotate 190° twice to accomplish rotating the needle 110 the full 360°)The actuation button 155 is operable so long as the device 50 is On andnot already in a suturing sequence. The actuation button 155 must bereleased and the Power-on button 154 re-depressed before depression ofthe Actuation button 155 will again begin the next suturing cycle. Theelectronic Hall Effect sensor 162 combined with the firmware sense theextent of the about 190 degree rotations utilizing the permanent magnetsin the drive wheel. Once the end of motion is detected the firmwaremodifies the torque applied to the motor to create a soft-stop. Some ofthe Error Modes that may occur during operation are listed in Table 1.

TABLE 1 Low Power Error Battery LED: Green Red Yellow REM Status: OffMode OFF OFF OFF Unit is off and will not actuate On Mode ON OFF OFFUnit is ready for use Actuating ON OFF OFF Unit is actuating through acycle. Error ON ON OFF Indicates an error occurred. Mode Mechanism willreturn to home position and not actuate if actuation button isdepressed. Recharge ON OFF ON Battery needs to be recharged uponRequired completion of surgery. I.e. unit can do 6 more completesutures. Battery ON ON ON Battery is drained. Unit will drained notactuate. Needs to be recharged. Charging OFF OFF Blinking Chargingcycle. Device will not Battery turn on or actuate while in this mode.Blinking rate TBD. Battery OFF OFF ON Battery charging cycle iscompleted Fully Charged

FIG. 30 is a close-up view of the stop plate 66 and drive wheel 67(shown as transparent), permanent magnets 65, the drive pin 63 and thegear 59 shaft. At the center of the stop plate 66 there is a hole whichprovides the entry point for the gear 59 shaft. The stop plate 66 isattached to the gear box 59 by screws 69. The stop plate 66 comprises a“U-shaped” track 64 in which the drive pin 63 rides. As the device isactuated, such that the electronic module causes rotation, the drive pin63 will ride along the track 64 until the drive pin 63 reaches astopping point. The track 64 provides the mechanical stops that limitthe rotation of the device 50. The permanent magnets 65 are used inconjunction with the Hall Effect sensor 162 located at a distal end ofan electronics board 161 located inside the removable electronic module60 to detect the rotational extents of travel. The electronic HallEffect sensor 162 combined with the firmware sense the extent of theabout 190 degree rotations utilizing the magnets 65 in the drive wheel67. Once the end of motion is detected the firmware modifies the torqueapplied to the motor 61 to create a soft-stop.

FIG. 26C shows the Hall Effect sensor 162 located on the electronicsboard 161 that is used to detect the rotational position of the drivewheel 67. When the rotation is nearing the stopping point, the magnets65 pass adjacent to the Hall Effect sensor 162, sending a signal to thecontrol electronics that the needle 110 will soon be stopping. At thatpoint the motor torque is reduced. The motor continues to drive to themechanical stopping point at the reduced torque level. When the drivepin 63 hits the mechanical stopping point, the control electronics sensethe current spike that is caused by the motor not turning any more andshut off the power to the motor. At least two magnets 65 are positionedin the drive wheel 67 to sense the approach to stopping points at bothends of the arc traveled by the drive wheel 67.

FIGS. 31A and 31B show the main components of the suturing device 50. InFIG. 31A the electronic module 60 has been drawn disengaged from thefront end assembly 70. During the disengaged stage, the torsion returnspring 77 is extended to allow the pusher assembly 71 to return to a“home” position. In the home position, the drive plate 80 returns to astart position, such that a hole 84 in the drive plate 80 is ready toaccept the drive pin 63. As shown in FIG. 31B the electronic module 60has been attached to the front end assembly 70. When the electronicmodule 60 is connected, the drive shaft 73 engages a bushing 67 alocated in the drive wheel 67; the drive pin 63 engages the hole 84 inthe drive plate 80 and the device 50 is ready.

FIG. 32A shows the curved suturing needle 110 having a tissue closingmaterial attached. The needle 110 is formed as a circular split ringwith the aperture (or gap) 111, the sharp, pointed end 112 and theopposite blunt end 113. The cylindrical bore 114 aligned axially withrespect to the needle 110, is located at the blunt end 113. A flexibleleader 136 of the tissue closing suture material is inserted into theblunt end 113 and can be restrained by mechanical engagement, forexample mechanical crimping. Those skilled in the art will recognizethat the flexible leader 136 may engage the needle 110 by any type ofmechanical engagement including, but not limited to, welding, soldering,or laser welding. For example, the assembly comprising the flexibleleader 136 inserted into the bore 114 of the needle can be immobilizedin a clamp, and the junction circumferentially welded with a YAG laserwelder or other suitable laser welder. The junction between the flexibleleader and wire monofilament suture similarly can be welded orlaser-welded. A suture-needle assembly welded in this manner can providea smoother transition between the needle and flexible leader, andbetween the flexible leader and the monofilament suture than mechanicalcrimping, which facilitates drawing the suture material through thetissue. Thus it is easier to pass the suture through the first side ofthe divided sternum, for example, while maneuvering the device 50 inpreparation for placing a suture in the second side of the dividedsternum. To enable the needle 110 to penetrate to the required depth,the needle 110 preferably has an arcuate extent between about 250° andabout 330°.

For suturing through bone, it may be preferable to have a triple-faceted(or ‘cutting-edge’) needle point as shown in FIG. 33A, each facetoccupying approximately 120° of the circumference of the needle shaft.As shown in FIG. 33B, One of the facets can be oriented to face theoutside curvature of the needle, in which case the outside-facing facetcan be cut at a shallower angle than the other two facets, preferably atan angle of approximately 21° with respect to the long axis of theneedle shaft. The resulting cutting surface of the needle point as shownin FIG. 33C will have a shorter cutting height, leading to moreefficient penetration of bony or other dense tissue. Alternatively, whenplacing the sutures around the outer or lateral edge of the sternum, theneedle tip can be configured with a ‘blunt taper-point’ or ‘ball-point’.The rounded tip and conical shape of the leading component of the needleshaft permits less traumatic penetration through softer tissues. Otherapplications may require sharper tipped ‘taper-point’ needles, or even‘reverse-cutting edge’ needles.

The needle 110 has two symmetric notches 115 a and 115 b along theradially rear edge, i.e. the edge proximal to the cartridge holderassembly. The notch 115 b is positioned toward the sharp pointed end 112of the needle 110. The notch 115 a is positioned toward the blunt end113 of the needle 110. The notches 115 a and 115 b are located oppositeto one another, each having a perpendicular (about 90°) segment and anangular segment that makes an angle of about 60° with the perpendicularsegment. The notches 115 a and 115 b are engaged by the drive mechanism(pawl) in the cartridge holder assembly 72 and enable the needle 110 toundergo a rotational movement upon actuation of the drive mechanism,causing the needle 110 to penetrate and advance through the spacespanning the split sternum, or other tissue location. A notch 116 islocated on the radially outer edge (“outer notch”) of the needle 110proximally to the notch 115 b that is closer to the sharp pointed end112. The outer notch 116 engages with an anti-rotate and locking barlocated in the cartridge holder assembly 72, whereby rotation of theneedle 110 in a direction opposite to the advancing direction or “needlebacking-up” is prevented. The positive engagement of the needle outernotch 116 during operation prevents the needle 110 from straying out ofsequence during the suturing process. In addition, the blunt end or hub113 of the needle 110 can also engage the anti-rotate bar 100 (or 300,if the device has a separate locking pin), as seen in FIG. 39C, toprevent the needle 110 from reversing direction after it has traversedthe aperture in the needle cartridge 90.

The needle 110 is enclosed within a cartridge, so the sharp pointed end112 is not exposed. This needle position, as loaded, is referred to asthe “home” position. In the home position, the needle 110 is fullycontained within the cartridge housing to eliminate needle-pricks duringhandling of the cartridge or the loaded device. The width of theaperture in the needle cartridge is comparable to and corresponds withthe width of the gap in the needle 110 so that when the needle 110 is inthe home position the needle 110 does not project materially into theaperture 111. Such an alignment causes the needle 110 to reside entirelywithin the needle cartridge, thereby preventing inadvertent contact ofthe sharp pointed end 112 with the user's fingers during handling of thedisposable needle cartridge for placement on the cartridge holderassembly or disposal after use, and while operating the suturing device50. Such protection of the needle 110 in the suturing device 50 preventsaccidental “needle-pricks” from occurring, thereby substantiallyreducing the risk of infection caused by pathogenic bacteria or virusesthat may contaminate the needle 110 during or after use prior todisposal. The needle 110 may be rotated in a curved track of the needlecartridge about the longitudinal axis of the suturing device 50 toadvance the pointed needle end 112 so that the needle 110 first spansthe aperture 111 and then returns to the home position.

FIG. 32B shows an expanded view of a crimp 137 that houses the ends ofthe two materials that form a tissue closure suture material. The tissueclosing material includes the flexible leader 136 attached to a wiresuture 138 by means of the crimp 137. The crimp has an opening on eachend, a first opening 137 a accepts the flexible leader 136 and a secondopening 137 b accepts the wire suture 138. The flexible leader 136 isplaced into the first opening 137 a and then the crimp 137 ismechanically crimped to engage the flexible leader 136. The wire suture138 is placed into the second opening 137 b and then the crimp 137 ismechanically crimped to engage the wire suture 138. Those skilled in theart will recognize that the crimp 137 may engage the flexible leader 136and the wire suture 138 by any type of mechanical engagement including,but not limited to, welding, soldering, or laser welding. The crimp 137has a curved shape to make it easier to slide through the holes. Thecrimp 137 is streamlined and low profile to travel through tissue,cartilage or bone.

The flexible leader 136 has a diameter (gauge) that is larger or equalto the diameter of the wire suture 138. The flexible leader 136 may beformed from a stainless steel material or by some other braided ormonofilament material. In an embodiment, the flexible leader 136 isformed from wire cable. In an embodiment, the length of the flexibleleader 136 is between about 8 inches to about 18 inches. The flexibleleader 136 may be longer than 18 inches. The flexible leader 136 acts toimprove ease of suture manipulation within the thorax, for example(under the sternum) during placement of each of the series of wiresternum closure sutures and thus make sternum closure faster and easier.The wire cable 138 may be formed from wire suture, such as stainlesssteel, made available in varying wire sizes, such as, for example, 5, 6,and 7. In an embodiment, the length of the wire suture 138 is at least18 inches and may be longer than 18 inches. As shown in FIG. 34, thecartridge 90, needle 110 and suture material 138 can form the componentsof a sterile kit, packaged in appropriate plastic/reinforced papermaterial 700, which preferably can be peeled open to lay out thecomponents onto a sterile field. The bottom web of the package can bethermoformable transparent plastic film, such as polyamide/polyethyleneor polypropylene/polyethylene. This allows the contents of the sealedpackage to be visible. The top web can be sterilizable paper, such asTyvek®, with a basic weight of about 60 gm/m² or more, allowing it to bepermeable to sterilizing gas, so that the cartridge 90, needle 110 andsuture material 138 can be sterilized from within the package. The topand bottom webs are sealed along the periphery of the package using asuitable adhesive. The package preferably can be opened by hand, usingpeel-open corners and peelable seams.

The suturing device 50 is designed to be held in the dominant hand ofthe medical professional. FIG. 35 shows an embodiment of a suturingdevice having an ergonomic handle 160. FIGS. 36A-C show aspects of thefront side of the device 50 with cartridge 90 attached. FIGS. 37A-D showaspects of the rear sides (FIGS. 37A and 37B), the bottom side (FIG.37C) and the top side (FIG. 37D) of suturing device 50 without thecartridge 90. FIG. 38 shows an embodiment of a suturing device having apistol-like handle 160. The handle 160 is supplied non-sterile to themedical professional. The hospital or office is responsible forsterilizing the device 50 by techniques known in the art, such asgravity steam sterilization, Steris and ETO. In an embodiment shown inFIG. 35, the electronic module 60 has been surrounded by a hollowhandle/body that includes an activator button and may also include flushports along the handle/body in order to provide a port of entry forcleaning fluids or suction such that the device 50 can be cleaned priorto or after use. In an embodiment shown in FIG. 38, the electronicmodule 60 has been surrounded by a different hollow handle that includesan activator button and may also include flush ports along thehandle/body in order to provide a port of entry for cleaning fluids orsuction such that the device 50 can be cleaned prior to or after use.Those skilled in the art will recognize that the battery pack 62 andelectric motor 61 can be placed anywhere in the handle and be within thescope and spirit of the presently disclosed embodiments.

FIGS. 39A, 39B, 39C and 39D show serial views of the “rear-drive” needleoperating drive mechanism operating within the distal end of thecartridge holder assembly. The “rear-drive” mechanism comprises thedrive arm 75 connected to a drive shaft that is capable of circularmotion so as to “sweep” along the circular inner edge of the cartridgeholder assembly. FIG. 39A shows the needle 110 in the “home” position.Initially, the pawl 95 has not made contact with the needle 110. Thedrive arm 75 moves to engage a notch 115 a in the needle 110 (referredto as rest position). As shown in FIG. 39B, the gate assembly 105 isresting at stop pin 106. Actuation of the device causes the drive shaftto rotate about 190° in a counterclockwise direction (referred to asposition #1), thereby causing the drive arm 75 to move circularly fromits “home” rest position and move up to and past the gate assembly 105,causing the gate assembly to pivot clockwise in the process so that thegate assembly 105 is now resting at the other stop pin 106. The needle110 is prevented from moving backwards by the anti-rotate and lockingbar 100. The needle 110, in this position, is referred to as in a“penetrating-state” of the needle 110 cycle. As shown in FIG. 39C, thepawl 95 has been disengaged from the notch 115 a and the drive arm 75continues to move circularly until it comes to rest once again in the“home” position, about 190° clockwise from position #1 (this newposition is referred to as position #2). The pawl 95 then engages thenotch 115 b. The gate assembly 105 has pivoted counterclockwise to restagain at the other stop pin 106. FIG. 39D shows the pawl 95 engaged inthe notch 115 b and the drive arm 75 continuing to move circularly untilit is about 190° clockwise from position #2 (this new position isreferred to as position #3). The gate assembly 105 has pivoted clockwiseagain to rest at stop pin 106. The needle 110 is pulled through thespace between the tissue gap (e.g., split sternum) and the closingmaterial follows. The drive arm 75 then returns back to the start homeposition by rotating 190° clockwise to the position shown in FIG. 39A.

In an embodiment, the handle of the suturing device 50 does not containbatteries, but is powered by electric power provided from outside thesterile field of the operating room (OR). In this external electricpower embodiment, the device is configured with an autoclavable motor inthe handle and a sterilizable power cord attached to the handle. Thedevice would be connected with the sterilizable cord to a power supplyunit that is located outside the sterile field in the operating room.That power unit would be plugged into wall power, and be able to convertthe wall power (i.e., 120 volts or 240 volts) to voltage levelsappropriate for the motor. The sterilizable cord transmits power to thehand-held unit which contains the motor and the needle drivingmechanics. In addition, the control electronics could also be located inthe external power unit rather than inside the handle. This change inconfiguration would reduce the size of the handle.

The suturing device 50 of the presently disclosed embodiments can beused for any procedure in which bony tissue or dense soft tissue closureis required. The tissue chosen should be sufficiently compliant topermit penetration by one of the variety of needle tips that can be usedwith the device. Other possible uses could include, for example, repairof injuries or incisions involving the attachment points of the rotatorcuff, quadriceps tendon, patellar tendon or Achilles tendon, and ribreapproximation after lateral thoracotomy. In some of these cases, itmay be advantageous to use non-metallic suture material attached to aneedle that is compatible with the cartridge 90, cartridge holderassembly 72, and pusher assembly 71 of the device 50. The non-metallicsuture material can include, for example, braided or monofilament nylon,prolene or Dacron, natural material such as silk or catgut, andsynthetic absorbable material such as polyglycolic acid, polyglactin,polyglyconate or polydioxone.

Using a sternotomy procedure as an example, prior to the procedure, thehandle of device 50 is sterilized in a hospital autoclave and deliveredto the operating room in the same manner as any other piece of sterilesurgical equipment. The battery pack 62 of the electronic module 60 hasbeen charged using a charger and is brought into the non-sterile area ofthe operating room. As part of the routine set up of the surgical fieldin the operating room, a surgical scrub nurse will open the sterilepackage containing the sterilized handle of device 50. The scrub nursewill then open the rear portal of the handle and will use standardpractice aseptic technique to present the open portal of the handle to acirculating nurse who is located outside of the sterile operating field.At this time, the scrub nurse can grasp a sterile funnel 600 by theflange 603 and insert it into the handle 160 of the device 50. Thecirculating nurse will take the fully charged electronic module 60 andinstall the module 60 into the open rear portal of the handle 160 usingstandard aseptic technique. The circulating nurse can then grasp theflange 603 of the funnel 600 and withdraw it from the handle 160, beingcareful not to make contact with any other component of the device 50.To assist in this procedure, the circulating nurse can withdraw thefunnel 600 by using a sterile forceps or clamp to grasp the flange 603.The scrub nurse will close the portal, securing and sealing theelectronic module 60 into the handle. The reusable device 50 is nowready for the loading of the disposable suture cartridge 90.

When it is time to close the sternum, the scrub nurse will open thesterile disposable suture cartridges 90 that will be used in the case (atypical package will be a 6-pack). One suture cartridge 90 is loadedonto the cartridge holder assembly 72 of the device 50. The device 50 ischecked to make sure that the power light 154 is OFF, none of the LEDlights 156 should be illuminated. The 10 o'clock and 2 o'clock slots onthe needle cartridge 90 are aligned with the 10 o'clock and 2 o'clocktabs on the cartridge holder assembly 72. The needle cartridge 90 isaligned with the cartridge holder assembly 72, pushed onto the cartridgeholder assembly 72, and then rotated counterclockwise to lock the needlecartridge 90 in place. The locking pin 200 comes into alignment with thelocking pin recess 202 of the cartridge 90, at which point the lockingpin 200 can engage the locking pin recess 202. The needle brace 500, ifpresent, can be removed from the cartridge 90 after it has been securedto the cartridge holder assembly 72. The Power On button 154 is thenturned on. The green LED will come on, indicating the device 50 isready. The actuation button 155 is then pressed to cycle the needle 110once, prior to placing the device 50 in the surgeon's hand. The device50 should cycle twice, causing the needle 110 to rotate one revolution.The device 50 is now ready to be used to place the first suture. Thescrub nurse will hand the device 50 to the surgeon who will perform thesuture placement process. Sutures are placed at the surgeon's discretionfrom top to bottom of the sternum. Typically about six to eight suturesare used to close the sternum. As an additional measure to enhance itsoperational safety, the device 50 can be programmed to have eachactuation cycle require the operator to press the Power-on button 154before pressing the actuation button 155.

To commence the sternotomy closure, any embodiment of the sternotomyclosure device 50 is placed at the site of the sternotomy such that thedevice 50 is between a first side and a second side of a split sternum,the typical starting point is around the manubrium 170 (or head) of thesternum as shown in FIG. 40. The surgeon will elevate one side of thedivided sternum with his or her left hand. The surgeon places and alignsthe opening (aperture) of the needle cartridge 90 over the cut edge ofthe sternum locating the penetration point he desires for the sutureunder the top of the cartridge opening. The surgeon can also use thelower edge of the cartridge holder assembly 72 to elevate the dividedsternum during the suturing, obviating the need to place his or her handunder the sternum. The needle will enter the sternum from the exterior(outside) of the patient. The surgeon presses the Power-on button 154prior to positioning the device 50, and then presses the actuationbutton 155 while holding the device 50 in the desired location. When thebutton 155 is pressed, the following actions occur: The electroniccontroller starts the motor and gearbox rotating clockwise. This motionis transferred from the inside of the electronic module to the driveshaft by the following chain of components: Gearbox shaft to drive wheelto drive plate to the drive shaft to the drive arm. The drive arm holdsthe pawl. The pawl engages the rear drive notch of the needle. As thedrive arm rotates through a first half circular arc, the pawl pushes theneedle through a first half of one rotation. This is the stroke thatpenetrates the sternum. When the drive arm reaches the end of a stroke,the drive arm stops. The drive arm will then reverse direction andreturn to a start position. As soon as the drive arm reaches the startposition, the drive arm stops again. The drive arm now starts to rotateclockwise again. The pawl picks up the front needle notch and pulls theneedle through the completion of a stroke. When the drive arm reachesthe end of this stroke, the drive arm stops. The drive arm will thenreverse direction and return to a start position. As soon as the drivearm reaches a start position, it stops again, and the device 50automatically powers down. The needle is now completely driven throughthe one side of the sternum. The flexible leader has been pulled intoand through the hole created by the needle. The surgeon will now rotatethe device 50 handle clockwise pulling the leader through the one sideof the sternum. The surgeon's left hand may be used to assist pullingthe flexible leader through the sternum. The surgeon will now elevatethe other side of the sternum. The surgeon places and aligns the openingof the needle cartridge 90 over the sternum bone locating thepenetration point he desires for the suture under the bottom of theneedle cartridge opening. After the surgeon presses the Power-on button154, followed by the actuation button 155, the needle will enter thesternum from the interior (inside) of the patient. The steps arerepeated. At this point, the flexible leader has passed through thisside of the sternum. The surgeon may press the cartridge locking surface101 located on the anti-rotate and locking bar and rotate the needlecartridge 90 clockwise to remove the needle cartridge 90 from the device50.

The device 50 may be passed to the scrub nurse for loading of a secondneedle cartridge 90. The surgeon will now use both hands to pull theflexible leader and suture through both sides of the sternum followingstandard practice for any sternum closure suture. The needle, flexibleleader and crimp ferrule are removed from the monofilament suture usingstandard practices. The surgeon now moves on to place a second suture.The process continues for all remaining sutures that the surgeon choosesto place, typically to an area near the xiphoid process 172. After alldesired sutures are placed, the sternum closure is completed usingstandard surgical techniques. The device 50 may be prepared forcleaning, sterilization and charging. A typical procedure may include:The clean up personnel will wipe down the outside of the device 50 witha disinfectant. The rear portal will be opened and the electronic modulewill be removed. The electronic module goes to non-sterile equipmentstorage for charging on the dedicated charger. The device handle will becleaned to according to a validated cleaning protocol. The device handlewill be sterilized according to a validated sterilization protocol.

A Teflon seal 57A or an O-ring seal 57 between the pusher assembly andthe cartridge holder assembly 72 provide a sterility barrier so thatwhen the pusher assembly is driving the needle, the drive shaft willrotate within the Teflon seal 57A or O-ring 57 which will preventanything from migrating down the drive shaft and finding its way insidethe handle of the tissue closure device 50.

A method for sternum re-approximation is provided herein. The methodincludes (a) releasably engaging a cartridge having a protective housingand a suturing needle to a cartridge holder assembly of a sternotomyclosure device; (b) placing the sternotomy closure device having thecartridge and the suturing needle to cause an aperture in the cartridgeto be between a first side and a second side of a split sternum, whereina pointed end of the suturing needle is positioned within the protectivehousing before and after a complete rotation of the suturing needleabout a rotational axis; (c) activating an electronic module coupled toa pusher assembly that releasably engages the suturing needle to causerotational movement of the suturing needle across the aperture in thecartridge and advance the suturing needle through the first side of thesplit sternum; (d) pulling a suturing material attached to the suturingneedle through the first side of the split sternum; and (e) repeatingsteps (c) and (d) for the second side of the split sternum forming astitch through the first side and the second side of the split sternum.Steps (b) through (e) are repeated until a length of the first side andthe second side of the split sternum have been re-approximated.

All patents, patent applications, and published references cited hereinare hereby incorporated by reference in their entirety. It will beappreciated that various of the above-disclosed and other features andfunctions, or alternatives thereof, may be desirably combined into manyother different systems or applications. Various presently unforeseen orunanticipated alternatives, modifications, variations, or improvementstherein may be subsequently made by those skilled in the art which arealso intended to be encompassed by the following claims. Thus, it isintended that the present invention include modifications and variationsthat are within the scope of the appended claims and their equivalents.

What is claimed is:
 1. A surgical suturing system comprising: a needleadvancement drive that reciprocates between a driven position and areturned position; an arcuate needle track to receive an arced suturingneedle to be advanced by the needle advancement drive; an electric motorconfigured to operate the needle advancement drive; and a control systemto control operation of said electric motor to operate said needlerotation drive, the control system including a controller including aprocessor, and a processor-readable tangible non-transient mediumcoupled to the control system, the processor-readable tangiblenon-transient medium storing a computer program for operating thesurgical suturing system, wherein the computer program comprises:instructions to operate the electric motor to cause the needle rotationdrive to engage the arced suturing needle to advance the arced suturingneedle along the arcuate needle track along a first direction, wherein aleading end of the arced suturing needle is positioned within aprotective housing of the surgical suturing system after the needleadvancement drive has reached the driven position; and instructions tocause the control system to detect a relative position of a portion ofthe needle rotation drive.
 2. The surgical suturing system of claim 1,further comprising an arced suturing needle defined at least in part bya leading end, a trailing end, an arced body between the leading andtrailing ends, and at least one engagement surface formed into theneedle.
 3. The surgical suturing system of claim 2, wherein the arcedsuturing needle is disposed in a cartridge that is removably coupled tothe surgical suturing system.
 4. The surgical suturing system of claim1, wherein the needle advancement drive is configured to be disengagedfrom the surgical suturing system at an attachment interface.
 5. Thesurgical suturing system of claim 4, wherein at least a portion of theneedle advancement drive is configured to be decoupled from the electricmotor by disengaging said at least a portion of said needle advancementdrive at the attachment interface.
 6. The surgical suturing system ofclaim 1, wherein the needle advancement drive includes a drive shaft. 7.The surgical suturing system of claim 6, wherein the needle advancementdrive further includes a flexible joint coupled to the drive shaftconfigured to transmit torque.
 8. The surgical suturing system of claim1, further comprising a drive shaft configured to transmit torquethrough a flexible joint.
 9. The surgical suturing system of claim 1,wherein the instructions for causing the control system to detect therelative position of the portion of the needle rotation drive compriseinstructions to process a signal received from a sensor that isconfigured to react to the relative position of the portion of theneedle rotation drive.
 10. The surgical suturing system of claim 9,wherein the computer program further comprises instructions to adjust anapplied torque level of said electric motor in response to said signal.11. The surgical suturing system of claim 10, wherein the computerprogram further comprises instructions to continue to drive said needleto a stopping point at a reduced applied torque level.
 12. The surgicalsuturing system of claim 11, wherein the computer program furthercomprises instructions to shut off electrical power to said electricmotor in response to a current spike caused by the electric motor notturning any further as a result of reaching the stopping point.
 13. Thesurgical suturing system of claim 9, wherein the sensor is anelectromagnetic sensor.
 14. The surgical suturing system of claim 13,wherein the sensor is a Hall Effect sensor.
 15. The surgical suturingsystem of claim 14, wherein passage of a magnet disposed on a portion ofsaid needle advancement drive past said Hall Effect sensor induces theHall Effect sensor to send the signal to the controller.
 16. Thesurgical suturing system of claim 2, wherein the needle advancementdrive includes a drive pawl that engages an indentation defined in thearced suturing needle to advance the arced suturing needle along saidarced needle track along the first direction.
 17. The surgical suturingsystem of claim 16, wherein the indentation is defined along a side edgeof the arced suturing needle displaced from a concave surface of thearced suturing needle.
 18. The surgical suturing system of claim 16,wherein the needle advancement drive further comprises a gear traindisposed between an electric drive motor and the drive pawl that engagesthe arced suturing needle.